Method for sealing paper cartons



June 2, 1 936. A. yvEsELMAN 2,043,135

METHOD FOR SEALING PAPER CARTONS Filed Nov. 4, 1932 Alberi wax/mu INVENTOR BY I Q A TORNEYS ucts, especially food products, formechandising' Patented June 2, 1936 UNITED STATES PATENT OFFICE METHODFOR SEALING PAPER CARTONS Albert wesselman, Cincinnati, Ohio ApplicationNovember 4, 1932, Serial No. 641,198

8 Claims.

The present tendency to package various prodthe same to the retail tradepresents various problems, one of which is the sealing of the contentsof the package or container in such manner that moisture from withoutshall not enter, that moisture from within shall not escape, and variousother .problems because of which it has been deemed necessary anddesirable to use sheet metal containers and the like in numerousinstances. For'reasons of economy paper or cardboard packages aredesirable as compared with sheet metal containers and the like, andbecause of that fact various improvements and treatments of paper andcardboard have brought the cardboard art to such a place that anordinary piece of cardboard may be rendered substantially impervious tomoisture, air, and vermin. Practical problems, however, have interferedwith the satisfactory commercial use of paper and cardboard containersthat are so treated because the producer and packer of various productsin cardboard and paper containers has been unable to provide aneffective seal at the time the carton or package is closed upon thecontents thereof. Because of this condition, there has grown up thepractice, particularly common in the breakfast food art, of providing aninner waterproof container, generally having a parafiine coating orimpregnated withparafline whereby to provide a substantially sealedinner container which in turn is placed in an outer container and whichouter container is not sealed against moisture, atmosphere, etc.

An object of this invention is to provide a means and method foraccomplishing in one container, the same result that is attained in thetwo containers referred to in the preceding paragraph, as being a commonexpedient in the breakfast food art. Y

Another object is to provide a simple and emcient solution of theproblem that will readily fit in with the present commercial practicesand which will not in any way interfere with or delay the packaging andhandling of goods.

Although the remarks heretofore made are directed primarily to thepackaging of food products, it is to be understood that reference tofood products is merely exemplary and is not made for the purpose ofrestricting the invention to that particular field or activity.

These and other objects are attained by the invention described hereinand disclosed in the accompanying drawing, in which:

Fig. 1 illustrates in perspective the ordinary or common rectangularcarton or package in which various products are quite commonly packed atthe present time. I

Fig. 2 is an enlarged side view showing one of the ends of a closedpackage such as illustrated in Fig. 1.

Fig. 3 is an enlarged sectional view online 3-3 of Fig. 2.

Fig. 4 is an illustrative view of one simple arrangement of mechanicaldevices that may be used in connection with the invention.

The carton lilexemplifles any kind of a paper box that has been treatedwith any of the various preparations for rendering the material thereofimpervious to moisture, atmosphere, and the like, and may be suitablytreated so that such vermin as would be expected to attackthe materialor the contents of the finished package, would retrain from such act.The package l0 would be filled with the articles or product that it isintended to carry into the market,'and the various flaps l I, I2, I3 andI8 would be folded upon one another and would be sealed or gluedtogether as is common practice at the present time in closing cartons orcontainers of the character described. This closing of the ends ofcontainers is done by machinery or mechanical means at a rapid rate andas a result thereof substantial openings or crevices result. It is notuncommon to have an opening at one or more of any of the eight coro nersof a container such as illustrated in Fig. 1, and through such openingsatmosphere and dust may pass.

After the package has been closed in any suitable manner, for example asexplained, the containers are sprayed with a quick-drying material thatfunctions both as an adhesive and as a plugging or sealing substance.This spraying is accomplished along the cartons between the indicatedeight corners. The manner in which the flaps II to M, inclusive, areturned in upon any particular type of carton will determine the placesand the extent upon which the spraying should be done. Ordinarily incartons wherein the smaller flaps such as I3 and M are turned in first,and over which larger flaps I l and i2 are then turned in, it would besufl'icient to spray the closed container along the crevices developedat the upper and lower extremities of the narrower sides I 5 of thecarton, incident to the indicated folding in of the flaps. In someinstances the nature of the stock from which the carton is made is suchthat the mere bending over or turningdown of the flaps such as l l to Hiinclusive, effects a breaking down to some degree of the paper stock orcard- 55.

board stock. and through such weakened or broken down portions thereof,it might be possible for air, dust and/or moisture to find their wayinto and out of the container. In instances where this may happen, thecartons 'or containers are preferably sprayed all around the upper andlower extremities of the carton at which places the various flaps arehingedly connected to the various body panels such as l5 and i6, of thecarton.

The material used for the indicated purpose may comprise any suitablematerials in view of the nature of the paper or cardboard stock fromwhich the container is made and in view of the nature of the articles orsubstances to be contained therein. In connection with containers usedfor food products, a material of a nitro-cellulose base may be used, andwith the same there may be employed a suitable solvent as in one of thenumber of alcohols that will permit ready spraying of the compositionthrough any of the commonly employed spray devices such as spraynozzles. Without limiting the use to any particular device or type ofspray device but merely for the purpose of indicating generally types ofspray device that may be used for this purpose, reference is made tosuch patents as De Vilbiss, No. 1,045,266, Day, No. 1,321,014, Wold, No.1,169,587, and ohers. In some instances it might be desirable to providean air current used in connection with the atomizing devices which is soconditioned that the sprayed material will dry almost instantaneouslywith contact thereof with the container. Spray devices of the characterreferred to are indicated generally by nozzles I! in Fig. 4. It may bedesirable in some instances to apply a slight pressure upon the ends ofthe containers at or about the time the sprays are directed along thecrevices of the container thereby holding the various layers ofoverlying flaps in position so that the sprayed material may functionmost efficiently as an adhesive for holding the layers together andthereby reducing the quantity of material necessary in order to effectan effective sealing and plugging of the indicated crevices. Suchpressure means may be of any suitable character and for purpose ofgeneral illustration of a simple means for accomplishing the indicatedpurpose, there is shown a pair of cooperating belts i8 and I9 thatjointly serve to convey or carry the containers past the spray nozzlesl1 and for exerting sufflcient compressive force upon the containers toattain the indicated pressing together of the flaps at the time thesealing material is applied. It is to be understood that any othermechanism for accomplishing similar results may be supplied in lieu ofthe belts l8 and I9 and that nozzles may be placed in other positionsthan those shown, it being obvious that if a spray is to be directedaround the upper and lower extremities of the four walls l5 and it, thata different arrangement of belts and nozzles may in some instances benecessary. The discharge of sealing material from the nozzles may becontrolled by the articles as they are carried along by the conveyorwhereby the nozzles efiect discharge only at such times when a packageis in position for treatment.

In Fig. 3 the sealing material is illustrated as indicated at 20. It isto be understood that with different packages a different relationshipof crevices and iiaps will exist and it is intended that the spray shallbe adequate to plug up all of these various openings and that the spraymaterial shall supplement the binding or retaining function of any ofthe various other adhesives that may be used in the first instance forclosing and adhesively securing the flaps Ii to H inclusive. In someinstances the entire adhesive agent used for holding the flaps inposition may be applied by sprays, however, generally this arrange mentwould not be feasible in any instances where the nature of the sprayingmaterial might injuriously affect the contents of the container in theevent that some of the material should be blown into the containerbefore the flaps are brought down into folded position as illustrated inFigs. 2 and 3.

At the present time it is quite common to provide a so called glossfinish to containers. and the spray material may be of such compositionthat when applied it will give a similar gloss effect to those parts ofthe containers that are sprayed. In some instances where the containersdo not have the gloss finish on the outside, it may be desirable to usea spray material that will not give a gloss effect when applied to thecontainer. At the present time paper containers, especially cardboardcontainers are somewhat extensively coated upon either the inside oroutside, and in some instances both inside and outside for obtaining acontainer that is substantially impervious to moisture, air, etc. andthe spray material must of course be such that it will not counteractthe indicated treatment as well asbeing of a nature such that it willreadily adhere to the painted container regardless of the treatmentthereof. Moreover, the spray material should be of such character I thatwhen dry, it is still somewhat elastic, it being obvious that if thematerial should be too rigid when applied, the accidental dropping ofcartons might fracture the seal and thereby defeat the attainment of theobjectives of the invention. Generally various lacquers meet thisrequirement. 'There are many varieties of lacquers and the variouscharacteristics thereof are quite well known wherefore it is to beunderstood that such lacquer will be used as will give the desireddegree of elasticity while at the same time attaining the adhesion andplugging effects.

What is claimed is:

1. The method of sealing fieidble containers comprising folding partsthereof upon one another for effecting a substantial closing of thecontainer whereby crevices are developed adjacent the folded parts andthen blowing a sealing and plugging material into the crevices.

2. The method of packaging products in paper and other fibrouscontainers having foldable parts between and along which parts, crevicesdo or may develop incident to the folding operation, and comprising thefolding of parts of the container, whereby crevices are developed alongthe folded parts andthen spraying a substantially atomized substance ofadhesive and cohesive characteristics into and along such crevices forclosing or plugging the crevices and for holding the container partstogether.

3. The method of closing and sealing cartons and the like comprisingfoldable flaps, and consisting of folding and adhesively securing thefiaps to close the container about the contents thereof whereby crevicesare formed adjacent the folded parts and then applying a spray ofmaterial of adhesive and cohesive characteristics along the foldableflaps for sealing or plugging the crevices developed incident to thefolding and initial securing operations.

4. The method of initially folding and adhesively securing togetherfoldable parts of a container whereby crevices are developed at thesurface of the container and adjacent said folded parts and thenapplying plugging and sealing adhesive material along the crevicesincident to said folding and securing operations, and apply-" ingpressure to the container alongside of said crevices during the pluggingand sealing operation. a

5. The method of treating containers having flexible parts folded uponone another whereby crevices are formed at the surface of the cont'ainerand adjacent to said folded parts, comprising the steps of applying anadhesive crevice filler along the crevices at the lines of folding ofthe said folded parts, and applying pressure to p the flexible parts tocontract the crevices during and after application of the crevicefiller.

6.vThe method of sealing flexible containers comprising folding theparts thereof .upon one another for effecting a substantial closing ofthe container, whereby crevices result adjacent to the folded parts,then directing into the crevices an adhesive filler in a form whichdries almost instantly upon contact with the container so as to enterthe crevices without materially entering the container interior.

"I. The method of sealing flexible containers comprising foig the :wthereof upon one another for effecting a substantial closing of thecontainer, whereby crevices result adjacent to the folded parts, thendirecting into the crevices an adhesive filler in a form which driesalmost instantly upon contact with the container so as to enter thecrevices without materially entering the container interior, the methodincluding also the step of applying pressure to the folded parts duringapplication of the filler whereby to further reduce the likelihood offiller entering the container interior.

8. The method of manufacturing a container, which comprises producingfrom a fibrous sheet material treated for exclusion of moisture, air,and vermin, a container body having foldable end closing flaps, foldingthe flaps upon one another whereby to form crevices at the surface ofthe container and adiacent to said folded parts, and applying aquick-drying adhesive filler at and about the folded end closing flaps,to dispose the coating between and about the adjacent folded end closingflaps and sealing the crevices and the interior of the container againstentry of external air, moisture or vermin at the places of fold andoverlap of the folded end closing flaps.

ALBERT WESSELMAN.

